Use of porous glass media for a biofilter to remove odorous compounds from an air stream

Abstract

A system for removing undesirable compounds from contaminated air includes a biofilter having porous glass media. Hydrogen sulfide is removed from contaminated air by passing the contaminated air through the biofilter.

What is claimed is: 
     
       1. A method of removing an undesirable compound from contaminated air, the method comprising flowing the contaminated air through a contaminated air inlet of a gas phase biofilter into the gas phase biofilter, the gas phase biofilter including a foamed glass media including from about 80% to about 90% empty space and having a density of about 0.2 grams/cm 3 . 
     
     
       2. The method of  claim 1 , further comprising filling a media bed compartment of the biofilter at least partially with the foamed glass media prior to flowing the contaminated air through the biofilter. 
     
     
       3. The method of  claim 2 , further comprising growing a population of hydrogen sulfide oxidizing bacteria on the foamed glass media. 
     
     
       4. The method of  claim 3 , further comprising maintaining the population of hydrogen sulfide oxidizing bacteria on the foamed glass media. 
     
     
       5. The method of  claim 3 , further comprising:
 measuring a concentration of nutrient in one of a fluid within and exiting the biofilter; and 
 adjusting an amount of nutrient added to the media bed compartment per unit of time responsive to the concentration of the nutrient in the fluid being outside of a predetermined range. 
 
     
     
       6. The method of  claim 1 , wherein removing the undesirable compound from the contaminated air comprises removing hydrogen sulfide from the contaminated air. 
     
     
       7. The method of  claim 6 , wherein removing the hydrogen sulfide from the contaminated air comprises reducing a concentration of hydrogen sulfide in the contaminated air by more than about 95% by passing the contaminated air at a flow rate of from about zero to about 250 cubic meters per hour per cubic meter of a media bed of the biofilter including the foamed glass media through the media bed. 
     
     
       8. The method of  claim 7 , wherein reducing the concentration of hydrogen sulfide in the contaminated air comprises reducing the concentration of hydrogen sulfide in the contaminated air by more than about 99%. 
     
     
       9. The method of  claim 6 , wherein removing the hydrogen sulfide from the contaminated air comprises reducing a concentration of hydrogen sulfide in the contaminated air by more than about 95% by passing the contaminated air at a flow rate of greater than about 500 cubic meters per hour per cubic meter of the media bed through the media bed. 
     
     
       10. The method of  claim 9 , wherein reducing the concentration of hydrogen sulfide in the contaminated air comprises reducing the concentration of hydrogen sulfide in the contaminated air by more than about 99%. 
     
     
       11. The method of  claim 1  wherein individual pieces of the foamed glass media have dimensions of between about 0.5 inches to about one inch across and include passageways extending from first surfaces of the individual pieces to second surfaces of the individual pieces. 
     
     
       12. A method of facilitating treatment of a contaminated air stream having an odorous compound in a gas phase biofilter, the method comprising introducing foamed glass media into a media bed of the gas phase biofilter, the foamed glass media including from about 80% to about 90% empty space and having a density of about 0.2 grams/cm 3 , individual pieces of the foamed glass media having dimensions of between about 0.5 inches to about one inch across and include passageways extending from first surfaces of the individual pieces to second surfaces of the individual pieces. 
     
     
       13. The method of  claim 12 , further comprising providing a drain from a sump of the biofilter for withdrawing waste fluid from the biofilter. 
     
     
       14. The method of  claim 12 , further comprising providing a connection on the biofilter to a source of the contaminated air stream. 
     
     
       15. The method of  claim 12 , further comprising providing a connection on tide biofilter to a source of water to be introduced onto the media bed. 
     
     
       16. The method of  claim 12 , further comprising providing a connection to a source of dilution air to be supplied to the biofilter. 
     
     
       17. The method of  claim 12 , further comprising providing a connection on the biofilter to a source of a nutrient to the biofilter to promote growth of sulfide oxidizing bacteria on the media. 
     
     
       18. The method of  claim 12 , further comprising providing a connection on the biofilter to a treated air outlet. 
     
     
       19. The method of  claim 12 , further comprising:
 providing a connection on the biofilter to a source of the contaminated air stream; 
 providing a connection on the biofilter to a treated air outlet; and 
 providing a connection on the biofilter to a source of water to be introduced onto the media bed. 
 
     
     
       20. The method of  claim 1 , further comprising controlling a ratio of contaminated air flowed in the gas phase biofilter through the contaminated air inlet to any dilution air introduced into the gas phase biofilter through a dilution air inlet responsive to an analysis of information provided from one or more sensors associated with the gas phase biofilter. 
     
     
       21. The method of  claim 1 , further comprising:
 measuring a pressure differential across the media bed; and. 
 responsive to the pressure differential exceeding a predetermined threshold, one of increasing a speed of a blower providing a motive force for air flow through the biofilter, shutting down the hiofilter, or providing an indication to an operator that the hiofilter may he in need of service.